There has been known techniques for building a virtual society on the Internet, and by use of which a virtual value is given to a virtual object existing in the virtual society, the virtual value is correlated with reality to provide a sense of reality, and exchange of possessions of clients is enabled on the basis of the virtual values to support economic activities in the virtual society, for operating a virtual society where a conversation activity of clients and activities such as participation in a game and management can be freely performed (refer to Patent Literature 1, for example.)    [Patent Literature 1] JP, 2002-259319, A